UPDATE from Cooler Master on battery life: The CK721 has the same power consumption thus have same working hours under 2.4GHz and Bluetooth mode due to below reason: Although the keyboard in 2.4G ...

Spill-Resistant Design B01N4EV2TL HP USB Wireless Spill Resistance Keyboard and Mouse Set Wireless 10m Working Range, 2.4G Wireless Technology B07V82W5CN cimetech Wireless Keyboard and Mouse ...